CVE-2026-16599 (GCVE-0-2026-16599)

Vulnerability from cvelistv5 – Published: 2026-08-25 14:17 – Updated: 2026-08-25 14:51
VLAI
Title
Denial of Service in GNU wget
Summary
GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network attacker positioned to intercept FTP traffic can send a crafted OPIE challenge with a sequence number near INT_MAX, causing wget to perform up to approximately 2.1 billion MD5 computations and suspend for some time. The --timeout option does not mitigate this because it applies only to network I/O, not CPU computation. This issue was fixed in commit e9697d98e7249b0f68a6be040a4f3dcc5bc101fa
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 14:38 UTC
CWE
  • CWE-606 - Unchecked input for loop condition
Assigner
CERT-PL CNA under the ENISA root
CNA scorecard B 81/100 over 222 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
GNU wget Affected: 0 , ≤ 1.25.0 (semver)
guessed Create a notification for this product.
Credits
Michał Majchrowicz (AFINE Team) Marcin Wyczechowski (AFINE Team)
Show details on NVD website
To clipboard 

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